Smoke eliminator

ABSTRACT

A box-like receptacle is supported in a generally horizontal plane intersecting a smoke containing heated gas stream. The receptacle is provided with vertically aligned openings in its upper and lower surfaces. Blower means within the receptacle forms a forced draft for the gas stream through the openings. An electrostatic precipitator unit is supported by the receptacle transversely of the gas stream direction of flow for collecting smoke forming particulates and cleaning the gas stream.

United States Glover et a1.

SMOKE ELIMINATOR lnventors: Boyd W. Glover; Harold N. Rainey,

both of Oklahoma City, Okla.

Assignee: Venus Electronics Corporation,

Oklahoma City, Okla.

Filed: Nov. 17, 1971 Appl. No.: 199,451

US. Cl. 55/126, 55/104;10s;139;14o;4 g,

481; DIG. 36, 98/115 K Int. Cl. 1303c 3/01 Field of Search 55/124, 126, 104, 55/108, 110,136,137, 138,139,140, 467, 481, DIG. 36; 98/115 R, 115 K, 36; 317/242; 178/79; 165/1 References Cited UNITED STATES PATENTS 7/1949 MacKenzie 317/242 X [45] Emily 2, 1973 2,709,954 6/1955 Baker 98/36 2,796,948 6/1957 Fields 55/137 3,469,031 9/1969 Setchell..... 178/79 3,618,659 11/1971 Rawl 165/1 3,654,747 4/1972 Remick 55/126 Primary Examiner-Dennis E. Talbert, Jr. Attorney-Robert K. Rhea [57] ABSTRACT A box-like receptacle is supported in a generally horizontal plane intersecting a smoke containing heated gas stream. The receptacle is provided with vertically aligned openings in its upper and lower surfaces. Blower means within the receptacle forms a forced draft for the gas stream through the openings. An electrostatic precipitator unit is supported by the receptacle transversely of the gas stream direction of flow for collecting smoke forming particulates and cleaning the gas stream.

5 Claims, 5 Drawing Figures SMOKE ELrMiNAToR BACKGROUND OF THE INVENTION 1. Field of the invention.

The present invention relates to electrostatic precipitators and more particularly to an apparatus for cleaning a smoke containing heated gas stream.

Most eating .establishments, such as restaurants, cafes, hamburger stands, or the like, use open burners or grills where the food is prepared and thus considerable smoke is emitted as heated exhaust gases as a result of burning fat or grease, such as is rendered from meats, or the like, while being cooked. The resulting heated gas stream is filtered to some extent by a screenlike filter suspended above the stove or burners but is principally used as a safety precaution in preventing fires and is inefficient in so far as removing the minute airborne particles visable as smoke. I

2. Description of the prior art.

Electrostatic precipitators are well known but so far as we know, no provision has been made for using an electrostatic precipitator in connection with eating establishments which may be easily and relatively inexpensively installed and operated to cleanse a heated gas stream of smoke forming or other airborne particulates in proximity with the source thereof.

SUMMARY OF THE INVENTION A box-like receptacle or housing, having longitudinal and transverse dimensions approximating the horizontal dimensions of a smoke producing source, such as burners, hotplates or a grill, is preferably disposed in a horizontal plane intersecting the normally vertical direction of a heated gas stream in spaced relation above the source. The housing is provided with upper and lower vertically aligned openings and includes a motor driven blower to form a forced draft through the housing openings. Adjacent its lower limit, the housing horizontally supports an electrostatic precipitator connected with a source of electrical energy for collecting all particulates contained by the gas stream. A gas stream intersecting screen is supported by the housing below the electrostatic precipitator. Means is provided for periodically removing and cleaning both the precipitator and screen.

The principal object of this invention is to provide an electrostatic precipitator support intersecting a heated gas stream and forming a forced draft for cleaning the gas stream.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective viewof the apparatus in operative position above smoke producing burners illustrated by dotted lines;

FIG. 2 is a fragmentary perspective view of the underside of the apparatus shown in FIG. 1;

FIGS. 3 and 4 are vertical cross-sectional views taken respectively along the lines 33 and 4-4 of FIG. I; and,

FIG. 5 is a wiring diagram.

DESCRIPTION OF THE PREFERRED EMBODIMENT Like characters of reference designate like parts in those figures of the drawings in which they occur.

The reference numeral indicates the device, as a whole, which is box-like in general configuration including a forward wall 12, a rearwall l4joined with end walls 16 and I8 and having top and bottom walls 20 and 22, respectively. A pair of transverse vertical partitions 24 and 26 extend between the front and rear walls 12 and 14 in spaced relation with respect to the respective end walls 16 and 18. The partitions 24 and 26 thus divide the receptacle to form a central chamber 27 and end chambers 28 and 29, respectively. The top wall 20 is centrally provided with a circular outlet opening 30. A generally U-shaped bracket or rack 31, having a bight portion 32 and legs 33, is disposed within the chamber 27 with the end portions of the legs connected to the depending surface of the top wall 20. The bight portion 32 supports a blower comprising a motor M having its drive shaft vertically disposed and connected with a fan F. The fan F is coaxially disposed within a ring 34 supported by the bracket 31l and coaxially aligned with the top opening 30. The depending wall 22 is centrally provided with a rectangular inlet opening 36 for admitting gas into the housing chamber 27 by the action of the blower.

A pair of channels 38 are cooperatively connected, respectively, to the inner wall surfaces of the partitions 24 and 26 above the plane of the housing bottom 22 with the legs of the channels facing toward each other for cooperative reception of a conventional rectangulat-shaped electrostatic precipitator unit 40 and a rectangular screen containing frame 42 which is horizontally disposed below the electrostatic precipitator.

The front wall of the housing is provided with an opening 43 between and vertically coextensive with the forwardly disposed edges of the partitions 24 and 26 which is normally covered by a closure lid or panel 44 coextensive with the housing front and hingedly connected at its upper edge to the forward edge of the housing top wall 20 for vertical pivoting movement about the axis of hinges 46, as shown by dotted lines (FIG. I). The panel 44 thus permits ease of access to the electrostatic precipitator 40 and screen 42 for removal and cleaning.

The housing is supported, in spaced relation above a heated gas and smoke producing unit 48, such as a grill, or the like, by a pair of L-shaped legs 50 connected at their upper end portions to the rearward wall 14 so that the foot portions 52 of the support legs project forwardly in parallel relation with respect to the plane of the bottom wall 22 of the housingand are supported by the surface supporting the grill, not shown.

The electrostatic precipitator 40 is conventional and may be purchased from Minneapolis-Honeywell Co., Minneapolis, Minn. The electrostatic precipitator is rectangular, fiat-like in appearence, containing a plurality of collector plates 53 and ionizing wires 54. The electrostatic precipitator is connected with a source of electric current AC by a pair of wires 60 and 61. A pair of ganged off-on switches 62 are interposed in the wires 60 and 61. The wire 60 is connected to the center poles 64 and 66 of a double-pole double-throw switch S. One terminal 68 of the switch S is connected to one end of a primary winding of a high voltage transformer T. The other source wire 61 is tapped to the primary winding of the transformer, intermediate its ends, with the remaining portion of the primary winding connected across a resonating capacitor C. Two terminals 72 and 74 of the switch S are connected in series to one terminal of the motor M with the other terminal of the motor being connected to the wire 61. The other terminal 76 of the switch S is connected in series with a resistor and rectifier and to an indicating lamp L and capacitor C2 connected in parallel with the wire 61. The secondary winding of the transformer T is connected to a rectifier R with its output connected by a wire 78 to the collector plates 53 through a suitable resistor so that the collector plates form alternately charged electrodes and a direct current difference in potential between any two of the collector plates. A wire 80, connected to the output of the rectifier R, is connected with the ionizing wires 54 to provide an ionized electrostatic field. The rectifier R is also connected to ground through a resistor and power on indicator lamp L2. The transformer T and associated wiring and components are preferably contained by the housing chamber 28 with the switch S and lamps L and L2 mounted on a suitable bracket 82 secured to the housing bottom wall 22 so that operation of the device may be easily controlled and lamp indication observed.

Operation In operation the device is installed substantially, as described hereinabove and shown in FIG. 1. In normal operation the switches 62 are closed and the switch S is closed with its contacts 68 and 72 so that the power on indicator lamp L2 is excited indicating normal operation of the motor M and electrostatic precipitator 40 herein a heated gas stream, not shown, drawn from the burners through the electrostatic precipitator 40 by the fan F and airborne particulates in the gas stream, are deposited on the collector plates 53. The electrostatic precipitator 40 must be periodically cleaned to remove the particulates collected thereby as well as cleaning the screen 42 which is accomplished by manual removal of the electrostatic precipitator and screen from the channel supports 38 after lifting the panel 44. The

electrostatic precipitator and screen are both washed and replaced within the channels 38. The switch S is then closed with its contacts 74 and 76 so that the motor operates the fan to generate a forced air draft across the screen and precipitator for evaporative air drying of these units prior to again energizing the electrostatic precipitator. During this action the lamp L is intermittently excited by built-up electrical potential discharged by the capicator C2 indicating that only the air drying feature is functioning. After a selected period of operation in this manner the switch S is again closed with its contacts 68 and 72 to resume normal operation.

Obviously the invention is susceptible to changes or alterations without defeating its practicability, therefore, we do not wish to be confined to the preferred embodiment shown in the drawings and described herein.

We claim:

1. A gas stream cleaning apparatus, comprising:

a rectangular housing having front, back and end walls joined with horizontal top and bottom walls;

a pair of vertical partitions dividing said housing and forming a central chamber and an end chamber at respective ends of the housing, said bottom wall having an inlet opening extending between the vertical planes of said partitions and said front and back walls,

said top wall having an exhaust opening communicating with the central chamber;

an electrostatic precipitator including a frame, collector plates and an ionizer;

connector means supporting said electrostatic precipitator frame within the central chamber adjacent the plane of said bottom wall;

blower means adjacent the exhaust opening for generating a forced draft through the central chamber inlet and exhaust openings;

an electric circuit connecting a source of electrical energy with said blower means and said collector plates and said ionizer; and,

mounting means positioning said housing in a gas stream.

2. The apparatus according to claim 1 in which said front wall is provided with an opening between the vertical planes of said partitions and adjacent the plane of said bottom wall,

said connector means including a pair of channel members connected, respectively, to the depending side surface of said partitions adjacent the plane of said bottom wall,

each said channel member having horizontal legs projecting toward the other said channel member for removably receiving said electrostatic precipitator frame; and,

a panel hingedly connected with the forward edge of said top wall and normally closing the opening in said front wall.

3. The apparatus according to claim 2 and further including:

a screen removably supported by said channel members below the plane of said electrostatic precipitator frame.

4. The apparatus according to claim 3 in which said blower means includes:

a U-shaped bracket having a bight portion and legs,

said bracket legs being connected, in depending relation, with said top wall;

a ring supported by saidbracket legs adjacent the edge of said top wall forming the exhaust opening;

a motor supported by said bight portion; and,

a fan driven by said motor.

5. The apparatus according to claim 4 in which said mounting means includes:

a pair of L-shaped legs having their longer portions vertically connected with said back wall, the foot portions of said L-shaped legs being horizontally disposed and projecting toward the vertical plane of said front wall. m k u 

1. A gas stream cleaning apparatus, comprising: a rectangular housing having front, back and end walls joined with horizontal top and bottom walls; a pair of vertical partitions dividing said housing and forming a central chamber and an end chamber at respective ends of the housing, said bottom wall having an inlet opening extending between the vertical planes of said partitions and said front and back walls, said top wall having an exhaust opening communicating with the central chamber; an electrostatic precipitator including a frame, collector plates and an ionizer; connector means supporting said electrostatic precipitator frame within the central chamber adjacent the plane of said bottom wall; blower means adjacent the exhaust opening for generating a forced draft through the central chamber inlet and exhaust openings; an electric circuit connecting a source of electrical energy with said blower means and said collector plates and said ionizer; and, mounting means positioning said housing in a gas stream.
 2. The apparatus according to claim 1 in which said front wall is provided with an opening between the vertical planes of said partitions and adjacent the plane of said bottom wall, said connector means including a pair of channel members connected, respectively, to the depending side surface of said partitions adjacent the plane of said bottom wall, each saiD channel member having horizontal legs projecting toward the other said channel member for removably receiving said electrostatic precipitator frame; and, a panel hingedly connected with the forward edge of said top wall and normally closing the opening in said front wall.
 3. The apparatus according to claim 2 and further including: a screen removably supported by said channel members below the plane of said electrostatic precipitator frame.
 4. The apparatus according to claim 3 in which said blower means includes: a U-shaped bracket having a bight portion and legs, said bracket legs being connected, in depending relation, with said top wall; a ring supported by said bracket legs adjacent the edge of said top wall forming the exhaust opening; a motor supported by said bight portion; and, a fan driven by said motor.
 5. The apparatus according to claim 4 in which said mounting means includes: a pair of L-shaped legs having their longer portions vertically connected with said back wall, the foot portions of said L-shaped legs being horizontally disposed and projecting toward the vertical plane of said front wall. 